JP4247883B2 - Seal material, manufacturing method thereof and valve - Google Patents

Description

表１の結果から、実施例１のシール材の耐久性が極めて優れていることがわかる。
【００３５】
〔別実施の形態〕
（１）シール材１の断面形状は、図に示したものに限定されるものではなく、外周側に膨出部を有する形状であればよい。
【００３６】
（２）上記実施形態では、円周コード２ａと巻付コード２ｂを同じ形状、材質のものを連続的に用いた例を示したが、これらは別々のゴム被覆コードから形成されていてもよく、又、形状、材質、巻回数などは必ずしも同一にする必要はなく、形状、材質、巻回数などを異なった構成としてもよい。用途、仕様により適宜変更可能である。
【００３７】
（３）上記実施形態では、バルブとしてバタフライバルブを例に挙げたが、本発明に係るシール材はこれに限定されるものではなく、各種バルブに適用可能である。
【図面の簡単な説明】
【図１】本発明に係るシール材の一実施形態を表す平面図
【図２】図１のシール材のＡ−Ａ断面図
【図３】シール材の製造方法を説明する図
【図４】シール材の製造方法を説明する図
【図５】図４のＢ−Ｂ断面図
【図６】ゴム被覆コードの製造方法を説明する概念図
【図７】ゴム被覆コードの形状例を示す断面図
【図８】従来技術のシール材を備えたバタフライバルブの動作説明図
【符号の説明】
２ ゴム被覆コード
２ａ 円周コード
２ｂ 巻付コード
２ｃ 芯材
３ 被装着部材の取付箇所[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sealing material, a manufacturing method thereof, and a valve. More specifically, the present invention relates to a disc-shaped rubber sealing material with a built-in reinforcing cord, a manufacturing method thereof, and a valve using the sealing material.
[0002]
[Prior art]
Various types of sealing materials such as rubber gaskets and packing are used in the pipes, valves or ducts through which fluid flows. Especially, diaphragms and lining materials are used for the valve sealing mechanism. Has been.
[0003]
Among these, the sealing material used for the valve sealing mechanism needs to withstand repeated strains of opening and closing operations and high sealing pressure, and requires high physical strength and large strain tolerance. In particular, as shown in FIG. 8, in the case of a butterfly valve 100 having a structure in which a rubber lip 11, which is a disc-shaped sealing material, is attached and sealed on the outer periphery of the valve body 10, when sealing with the valve seat 13 of the valve pipe 12. The rubber lip 11 is subjected to a large strain.
[0004]
Therefore, a sealing material in which polyamide short fibers having a diameter of 1 to 50 μm and a length of about 0.5 to 10 mm are uniformly dispersed and contained as a reinforcing material in rubber has been proposed (Patent Document). 1, 2).
[0005]
[Patent Document 1]
Japanese Patent Publication No.59-20704 [Patent Document 2]
Japanese Patent Publication No. 2-16339 [Problems to be Solved by the Invention]
However, in the above-described conventional sealing material, since the flowing fluid and the short fibers in the sealing material are in contact with each other, the deterioration of the short fibers occurs, the life of the sealing material is shortened, and high pressure is applied. However, the short fibers are oriented in the circumferential direction at the time of processing, so that the reinforcing effect of the rubber lip holding portion is not necessarily high, and there is room for improvement.
[0006]
Accordingly, in view of the above-described problems of the prior art, the object of the present invention is to provide a sealing material that does not expose fibers on the surface in contact with the fluid, has high pressure resistance, and has a high reinforcing effect on the rubber lip holding portion, and its manufacture. It is to provide a method and a valve.
[0007]
[Means for Solving the Problems]
The above object can be achieved by the inventions described in the claims. That is, the characteristic configuration of the sealing material according to the present invention is that the reinforcing cord is made of rubber having a disk shape with a built-in reinforcing cord, the reinforcing cord is configured by covering a long fiber with rubber, and in the circumferential direction. A circumferential cord arranged with a double structure on the inner and outer circumferential sides of the disk, and a wound cord wound in the circumferential direction so as to be sandwiched while intersecting the circumferential cord of the double structure It is composed of
[0008]
According to this configuration, since the reinforcing cord is built in and is not exposed to the surface in contact with the fluid, the reinforcing fiber is not deteriorated during use, and the combination of the circumferential cord and the winding cord, The inside of the sealing material can be reinforced with high uniformity and has high durability against severe loads.
[0009]
As a result, it was possible to provide a sealing material that does not expose fibers on the surface in contact with the fluid, has high pressure resistance, and has a high reinforcing effect on the rubber lip holding portion.
[0010]
A mounting location for the mounted member is formed, and the circumferential cord is arranged with a double structure on the inner peripheral side and the outer peripheral side of the disk so as to sandwich the mounting location from the radial direction, It is preferable that the circumferential cord is wound while the winding cord is along the inner circumferential side of the attachment location.
[0011]
According to this configuration, even if the reinforcing cords are arranged more uniformly and a severe load is applied, partial damage is less likely to occur, and the integral retainability when mounted on a mounted member such as a butterfly valve Becomes higher.
[0012]
Further, the characteristic configuration of the manufacturing method of the sealing material according to the present invention is that, in the manufacturing method of the rubber sealing material having a reinforcing cord and a disk shape, the reinforcing fiber is used as a core material, and an unvulcanized rubber is provided around the reinforcing fiber. The coated rubber-coated cord is arranged with a double structure on the inner and outer peripheral sides of the disk in the circumferential direction to form a circumferential cord, and the double-structured circumferential cord is sandwiched between them. In this way, the rubber-coated cord is wound to form a wound cord, rubber is injected into the rubber-coated cord to cover the rubber-coated cord in a disk shape, and then heated and vulcanized.
[0013]
According to this configuration, it is possible to provide a manufacturing method of a sealing material that does not expose the fiber on the surface in contact with the fluid, has high pressure resistance, and has a high reinforcing effect on the rubber lip holding portion.
[0014]
The circumferential cord is disposed with a double structure on the inner peripheral side and the outer peripheral side of the disk so as to sandwich the mounting equivalent portion of the mounted member from the radial direction, and the winding cord is attached to the attachment equivalent portion. It is preferable that the circumferential cord is wound along the inner circumferential side.
[0015]
According to this configuration, it is possible to manufacture a sealing material in which the reinforcing cords are arranged more uniformly, and when the cord is attached to a member to be attached, the integral retention is increased and the durability is further improved.
[0016]
Furthermore, the characteristic structure of the valve is that the seal material of claim 1 or 2 is used.
[0017]
According to this configuration, it is possible to provide a valve that does not expose the fiber on the surface in contact with the fluid, has high pressure resistance, and has a high reinforcing effect on the rubber lip holding portion.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a planar structure of the sealing material 1 attached to a butterfly valve arranged in the pipe 12, and FIG. 2 shows a cross-sectional structure of the sealing material 1 shown in FIG.
[0019]
This sealing material 1 is, for example, a donut-shaped disk shape to be attached to the outer peripheral edge of a butterfly valve (not shown), and is attached to a butterfly valve which is a kind of attached member. A plurality of bolt holes 3 are attached at substantially equal intervals along the outer peripheral surface. And the whole is formed with rubber | gum, and has the characteristic by which the reinforcement cord was embed | buried inside. The reinforcing cord is composed of a rubber-coated cord (topping mono cord) 2 in which high-strength fibers are used as a core material and unvulcanized rubber is coated thereon. As shown by a broken line in FIG. 1, the embedded rubber-coated cord 2 includes a circumferential cord 2a disposed on the outer peripheral side and the inner peripheral side with the bolt hole 3 interposed therebetween, and the circumferential cord 2a. And a winding cord 2b wound so as to be sandwiched while intersecting.
[0020]
That is, the winding cord 2b winds the inner circumferential side circumferential cord 2a on the inner circumferential surface side of the bolt hole 3 with respect to the double circumferential cord 2a, and further, the middle point between the two bolt holes 3 Thus, the outer circumferential side circumferential cord 2a is wound from the outer circumferential side, and this is repeated in the circumferential direction, thereby winding the circumferential cord 2a while intersecting the circumferential cord 2a. Since the sealing material 1 is configured in this way, the reinforcing fibers are evenly arranged inside the donut-shaped disk, and when this is mounted on the butterfly valve, the reinforcing fibers are on the surface in contact with the fluid. Without being exposed, it has a high physical strength and a large strain tolerance even under severe conditions, so that the reinforcing effect of the rubber lip holding portion can be enhanced. A method for manufacturing the rubber-coated cord 2 will be described later.
[0021]
Examples of the high-strength fiber include various organic fibers such as aramid fiber, nylon fiber, polyester fiber, and rayon fiber, inorganic fibers such as glass fiber and carbon fiber, and metal fibers such as steel fiber.
[0022]
As the covering rubber, natural rubber, butyl rubber, butadiene rubber, styrene butadiene rubber, ethylene propylene rubber and the like can be used. The rubber may contain butyl halide, other rubbers for improving properties, and various additives. Specifically, reinforcing materials such as carbon black and silica, inorganic fillers such as calcium carbonate, process oils and plasticizers, anti-aging agents, processing aids, vulcanizing agents, vulcanization accelerators, crosslinking modifiers, heat Examples thereof include plastic resins.
[0023]
Next, a method for manufacturing the sealing material 1 of the present embodiment will be described with reference to FIGS. A method for manufacturing the rubber-coated cord 2 will be described with reference to FIG.
[0024]
As shown in FIG. 3, a rubber-coated cord 2 in which unvulcanized rubber is coated around a high-strength fiber that is a reinforcing fiber, and a circumferential cord 2 a is formed so as to form a double disk shape in the radial direction. Next, the rubber-coated cord 2 is formed so as to be sandwiched between the circular cords 2a formed in a double disk shape and along the inner peripheral side of the bolt hole corresponding portion which is a portion corresponding to the attachment of the mounted member. Is wound into a winding cord 2b (FIG. 4). The winding pitch or the like of the winding cord 2b is appropriately selected depending on the use and specifications as the sealing material. As shown in FIG. 5, the BB cross-sectional structure in FIG. 4, the rubber-coated cord 2 is composed of a core material 2 c made of high-strength fibers and a surrounding rubber 2 d. Such a rubber-coated cord 2 can avoid the occurrence of contact wear and fatigue between fibers at a place where the circumferential cord 2a and the winding cord 2b are in contact with each other as compared with the case where only the fibers are arranged, Even when vulcanizing while applying pressure, a gap with the injected rubber is unlikely to occur, which is preferable.
[0025]
The rubber-coated cord 2 is manufactured as shown in FIG. In other words, a die 4 is attached to the tip of the cylinder portion 8 of the extruder E, and the high-strength fiber 2c unwound from a reel or the like (not shown) is fed to the die 4 and is not here. The vulcanized rubber composition is coated as the coated rubber 2d and sent out as the rubber-coated cord 2. As the high-strength fiber 2c, either a stranded wire or a single wire can be used.
[0026]
An example of the cross-sectional shape of the rubber-coated cord 2 is shown in FIG. In general, the circular shape shown in FIG. 7C is preferable, but various cross-sections can be used depending on the application. 7A shows an example having a cross section close to a rhombus or a parallelogram, FIG. 7B shows a square, FIG. 7C shows a circle, and FIG. 7D shows a trapezoid. In any case, the high-strength fibers 2c are covered with an unvulcanized rubber composition 2d.
[0027]
The rubber-coated cord 2 configured as described above is placed in a mold, injected to laminate the rubber, and then heated and vulcanized while being pressurized to obtain a donut-shaped disk-shaped product in which bolt holes are formed. . With this configuration, the reinforcing cords are arranged substantially uniformly on the disk-shaped product, and even if a severe load is applied, partial damage is less likely to occur, and the integral retention when mounted on the butterfly valve is improved. Increases durability and durability.
[0028]
【Example】
Example 1
A rubber-coated cord produced by coating a monocord of aramid fibers of about 1260 denier with natural rubber using an apparatus as shown in FIG. 6 is arranged as shown in FIG. The doughnut-shaped disc-shaped sealing material having an outer diameter of about 405 mmφ, an inner diameter of about 316 mmφ, and a bolt hole diameter of about 18 mmφ × 8 pieces was manufactured by injecting, coating, and vulcanizing while applying pressure. The thickness of the flat portion of the sealing material is about 12 mm, and the outer diameter of the outer peripheral spherical portion is about 25 mmφ. The rubber hardness was 60 degrees.
[0029]
This sealing material is attached to the butterfly valve body, attached to the valve seat with a sealing pressure of about 1.5 Mpa, placed in a pipe having an inner diameter of about 423 mm, and exposed to 60 ° C. hot water with a fluid pressure of about 0.2 Mpa. The durability was tested under the conditions of repeated sealing 24 times / day.
[0030]
(Comparative Example 1)
The same durability test was performed with the same shape as in Example 1 except that natural rubber having a rubber hardness of 60 degrees was used as the constituent material of the sealing material.
[0031]
(Comparative Example 2)
Except for using a natural rubber having a rubber hardness of 60 degrees and containing 2 parts by weight of an aramid short fiber having a length of about 3 mm and a diameter of 6 to 10 μm as the constituent material of the sealing material, the shape is the same as in Example 1, and the same Durability tests were conducted.
[0032]
(Comparative Example 3)
The same material as in Example 1 was used except that a long fiber (monocord) of about 200 denier as a reinforcing cord was used as a constituent material of the sealing material, and the density was 50/30 mm. A similar durability test was conducted.
[0033]
The results are shown in Table 1.
[0034]
[Table 1]

From the results in Table 1, it can be seen that the durability of the sealing material of Example 1 is extremely excellent.
[0035]
[Another embodiment]
(1) The cross-sectional shape of the sealing material 1 is not limited to that shown in the figure, and may be a shape having a bulging portion on the outer peripheral side.
[0036]
(2) In the above embodiment, the circumferential cord 2a and the wound cord 2b are continuously used in the same shape and material, but they may be formed from separate rubber-coated cords. Also, the shape, material, number of windings, etc. are not necessarily the same, and the shape, material, number of windings, etc. may be different. It can be appropriately changed depending on the application and specifications.
[0037]
(3) In the above embodiment, the butterfly valve is taken as an example of the valve. However, the sealing material according to the present invention is not limited to this but can be applied to various valves.
[Brief description of the drawings]
FIG. 1 is a plan view illustrating an embodiment of a sealing material according to the present invention. FIG. 2 is a cross-sectional view taken along line AA of the sealing material in FIG. FIG. 5 is a cross-sectional view taken along the line BB in FIG. 4. FIG. 6 is a conceptual diagram illustrating a method for manufacturing a rubber-coated cord. FIG. 7 is a cross-sectional view illustrating a shape example of the rubber-coated cord. FIG. 8 is an operation explanatory diagram of a butterfly valve equipped with a sealing material of the prior art.
2 Rubber-covered cord 2a Circumferential cord 2b Winding cord 2c Core material 3 Installation location of mounted member

Claims (5)

In a rubber sealing material having a disk shape with a built-in reinforcing cord, the reinforcing cord is formed by covering a long fiber with rubber, and a double structure on the inner and outer circumferential sides of the disk in the circumferential direction. And a wound cord wound in a circumferential direction so as to be sandwiched while intersecting with the double-structured circumferential cord. Wood. An attachment location for a member to be attached is formed, the circumferential cord having the double structure is arranged so as to sandwich the attachment location from the radial direction , and the winding cord is along the inner peripheral side of the attachment location. The sealing material according to claim 1, wherein the circumferential cord is wound. In a method for manufacturing a disc-shaped rubber sealing material with a built-in reinforcing cord, a rubber-coated cord with a reinforcing fiber as a core material and coated with unvulcanized rubber around it is arranged on the inner circumference side of the disc in the circumferential direction. And a double cord structure on the outer peripheral side to form a circumferential cord, and the rubber-coated cord is wound to sandwich the double cord circumferential cord while crossing to form a wound cord. A method for producing a sealing material, in which rubber is injected into the disc to cover the rubber-coated cord in a disk shape, and then heated and vulcanized. The circumferential cord having a double structure, as well as placed so as to sandwich the mounting corresponding portions of the mounting member from the radial direction, the circumferential cord while along the corded the wound on the inner peripheral side of the mounting corresponding portions The manufacturing method of the sealing material of Claim 3 which winds.   A valve using the sealing material according to claim 1.

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